The accident happened just after 10am (AEDT) as a Bendigo-bound train with 90 passengers aboard, including a group of primary school-aged children, prepared to leave from platform six.

In what witnesses described as a jarring thud, the stationary Bendigo train was slammed from behind by a Bacchus Marsh train as it moved into the platform to collect passengers.

Bruce Fraser, who was in the last carriage of the Bendigo train which received the full force of the blow, said he knew immediately they had been hit by another train.

"I knew we got hit by a train; that's all that could have hit you on the rails."

"It was a huge jolt, the train went straight into the back of it and it went bang," Mr Fraser said.

He said many other passengers in his carriage were injured.

"Most of the people were seated, but if you had been standing up you would have got hurt," Mr Fraser said.

"It could have been worse. If it had had a lot of speed, we would have been in big trouble."

Mr Holman said injuries were confined to those travelling in the train's rear carriage, with passengers ranging from a 12-year-old girl to a 69-year-old man who were ferried to city hospitals.

"Most of the people were distressed, but the paramedics were pretty quick on the scene ... our jobs is to sort the calm from the chaos," Mr Holman said.

He said injuries could have been far more serious had the train been going faster.
"Certainly had the impact been any greater it would have been much worse," he said.

Country rail carrier V/Line said an independent inquiry would be launched to investigate the cause of the accident.

V/Line managing director Andrew Neal apologised to passengers but refused to speculate on the cause of the accident.

"This is not a serious incident. This is a very minor collision that took place at quite low speed, the injuries we understand have been very minor at this stage.

Mr Neal said while reconstruction work took place at Spencer Street Station it was regular practice to have a number of trains leaving from the one platform.

"Clearly it (construction work) is having an impact on our operations, we are having to move platforms around, we've had tracks moved .... I don't believe it has had any impact whatsoever on the safety of our operations."

The train smash follows an incident in February when an unmanned runaway suburban train slammed into a stationary country train at Spencer Street Station.

Mr Neal said he was not concerned that a report from that accident had not been finished yet.

"If you try to set time limits on inquiries then you end up with shortcut results, people try and find the solution to fit the crime when in fact you may make it worse."